Expanding drill-bit for artesian-well boring



(No Model.)

o. C. LANL.

EXPANDING DRILL BII1 FOR ARTESIA'N WELL BORING.

No. 326,661. Patented Sept. 22, 1885.

mmmmmmmmmm UNITE STATES CHARLES C. LANE, OF SAI\T FRANCISCO, CALIFORNIA.

EXPANDING DRILL-BIT FOR ARTESlAN-WELL BORING.

f 'GN forming part of Letters Patent No. 326,661, dated September 22,1885.

Application filed December 29, lSl.

To all whom it may concern.-

Be it known that I, OHARLEs C. LANE, of the city and county of SanFrancisco, and State of California, have invented an Improvement inExpanding Drill-Bits for Artesian-VVell Boring; and l hereby declare thefollowing to be av full, clear, and exact description thereof.

My invention relates to a new and useful expanding or extension drillbitspecially adapted for use in boring Artesian wells; and my inventionconsists in two or more spring legs firmly secured at their tops to thehead of the tool, their lower ends being formed into or provided withcutters, above which, on their outer` edges, are formed peculiarfrictional or bearing knees in a tixed orstationary fulcrum-blockbetween the legs, over which they are adapted ends are forced together,whereby the distance between the cutters is made shorter than thedistance between the knees, and in a vertically adjustable automaticstrut-brace adapted to operate between the legs to hold them rigidlyseparated, and to release them when the tool has to be raised.

It consists, further, in providing in some cases anti-friction rollersfor the knees and a clamping-band for the cutters, and in other detailsofconstruction, all of which I shall explain.

In Artesian well boring the drill -bit is passed vdown on the inside ofthe pipe until its cutting points or ends project below the pipe. Thedrillis then rotated by suitable mechanism, and as it makes its hole thepipe is forced down after it. In ordinary drill-bits it is 0bvious thatas they are no wider than the interior diameter ofthe pipe the hole madeby them is also of that size, and therefore the pipe, which for thespace it ccupies is measured by its exterior diameter, has to be forceddown a hole too small for it. To obviate this difficulty, extension orexpansion drill-bits have been attempted. These are adapted to pass downthrough the pipe in a contracted condition, and when they get beyond thepipe they expand or extend in order to cnt a hole larger than the pipeitself, but it is obvious that the friction of the descending drill-bitagainst the interior wall of the pipe as it is being lowered ismaterially increased by the tact that it is being held in a contractedcondition, merely by reason ofits confinement within the pipe.

to bend when their lower] (No model.)

It is the object of my invention to overcome these various difficultiesby providing a drillbit which, though in its downward passage it iscontracted by reason of its confinement, will generate, nevertheless,the least amount of friction, and will expand or extend when it projectsbelow the pipe,whereby it is adapted to cut a hole larger than the pipeitself.

Referring to the accompanying drawings, Figure l is an elevation of mybit, showing it within the pipe. Fig. 2 is an elevation ofthe bit,showing it below the pipe and expanded. Fig. 3 is a detail view showingthe lower end of the bit and the band I applied to it.

The drill-bit has two or more legs, B, the tops of which are firmlybound to the head A of the tool, and the lower ends are formed intocutters or points C for boring. t rlhese legs are of a length sufficientto insure or allow of their having a slight spring, whereby theircutters or points C may be forced closer together. The legs divergetoward the bottom, their inner or adjacent edges being approximatelystraight, except near the bottom, where they curveinwardly,whence theyproceed approximately straight again. the inward curves join thesucceeding straight edges small shoulders b are made. Their outer edgesfor a certain distance from the top are parallel, approximately, withtheir inner edges to a point a little below the shoulders b, anddesignated by D, forming the k nees,which are rounded off, whence theyextend downward about parallel with the inner edges or slightly curvedto the cutters C.

In the normal or expanded condition of the legs, Fig. 2, it will be seenthat because they diverge, the distance between the outer edges of thecutters C is greater than the distance between the knees D, and thisfact would lead to adiftlculty in the passage of the drill-bit down thepipe, as its cutting-points would forni the only frictional bearingbetween it and the pipe. This is not desirable, not only on account ofthe tendency to injury which the cutters would sustain, but also becausesaid cutters would come in contact with and catch upon the joints of thepipe, which is constructed of sections screwed into one another. Toremedy these difficulties, I place between the legs at a point alittleabove their centers the fnlerum block or bar E, which At the pointswhere' IOO may be secured in any suitable manner, as by the forked rod eextending from the head of the bit; This block may be of wood or-othermaterial, and even of hard rubber or other elastic substance, in orderto take up the spring of the legs in a better manner and to stiffenthem. l This block serves. principally, however, as a fulcrum, overwhich the legs may bend when their cutter-points are forced together.`rlihe effect of this bending is to make the distance between thecutter-points shorter than the distance between the knees when the drillis in a contracted condition. This is shown in Fig l, where the drillbitis conned by the pipe F. It will be seen that the knees now form thefrictional bearingsurface, while the cutter-points are free of the pipe.The knees being rounded do not create much friction, and are subject tono injury. In some cases the anti-friction rollers G may be set into theknees,which will cause them to ride over the jointsl of the pipe withease andv lessen t-he friction in the'passage downward of the bit. rlheshape of the legs enables the drill-bit when being raised into the pipeto close its cutting-points and present its knees to the pipe, wherebythe points are saved in hoisting as well as lowering. In order to limitand adjust the separation of the legs, I have the link H, which preventsthem from spreading beyond what `may be desired. In some cases it may befound necessary to place the clampingband I on the cutters or points C,Fig. 3. vThis consists of a strip of metal hav- 'ing bent ends adaptedto engage suitable sockets or notches, t', in the points C, whereby thesaid points may be drawn together to such an extent as to relieve whollyor in part the knees D from friction. A few strokes of the bit when inposition cuts away the band I, and the cutters spread to the propercutting width.

By varying the shape of the cutters the implement may be used as areamer. It will be found necessary to make the legs of the tool whenseparated and doing work as rigid as possible in their expanded orextended condition, as they would have a tendency to be forced togetherat times. But whatever device be used to effect this result itis obviousthat it must release the legs when the tool is being let down or drawnup. Secured to the block E is a tube, J, extending downwardly to a pointjust below the limiting link. Secured to this tube at about its centeris a short bar, K, to the ends of which the levers L are pivoted. Io thetops of these levers are pivoted the outwardly-curved levers M, havingpivoted to their tops the levers N, the tops of which are pivoted to theheado of the spindle O. The spindle passes down loosely through tube J,and carries on its lower end a bar, l?, which is adapted to find a seatin the shoulders b, whereby it acts as a strut-brace to hold the legsrigidly separated. As the tool descends through pipe F the contactbetween the curved levers lVI and the pipe forces said levers to gether,thus elongating the system of levers; but as the lower ends of thesystem are pivoted to a xed point their upper ends alone rise, thuscarrying up the spindle and holding the strut-brace above its seat; butwhen free of the pipe the weight of the spindle causes its brace todescend to its seat, whereby the legs are held firmly separated. Inrising again the system of levers upon entering the pipe elongate andwithdraw the brace, whereby the legs may be forced together by theirknees entering the pipe.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

l. In a well-boring expanding drill-bit, the divergent spring legs B,rmly secured-attheir tops to the 4head of' the tool and havingcutters Cformed on their lower ends, in combination with the links -IzI betweensaidlegs,by which their divergence is limited, substantially as hereindescribed.

` 2. In a well-boring expanding drill-bit, the combination of thedivergent spring legs B, the tops of which are firmly bound to the headof the tool and their lower ends formed linto cut-ters C, said legshaving on their outer edges, above-the cutters, the knees D, asdescribed, and the fixed or stationary fulcrumblock E between said legs,over which they are adaptedv to bend when their lower ends are forcedtogether, whereby the distance between the cutters is made shorter thanthe distance between the knees, substantially as and for the purposeherein described.

3 In a well-boring expanding dri1lbit, the combination of thedivergentspring legs B, the tops of which are firmly bound tothe head ofthe tool and the lower ends formed IOO into cutters C, said legs havingon their outer edges, above the cutters, the knees D, the anti-frictionrollers G, mounted in said knees, and the xed or stationaryfulcrum-block between'said legs, over which they are adapted to bend,substantially as and for the purpose herein described.

4. In a well-boring expanding drill-bit, the divergent spring legs B,the tops of which are rmly bound to the head of the tool and their lowerends formed into cutters C, in combina- IIO tion with a mechanism bywhich the legs are i held rigidly separated when at workA and 'relievedwhen passing down or up the pipe, consisting of a strut-brace adapted tofind a seat between the legs and a system of pivoted extensible leversoperated by contact with the pipe to withdraw the brace and adapted toseat it when free of the pipe, substantially as herein described.

5. In a well-boring expanding drill-bit, the

divergent spring legs B, the tops of which are firmly bound to the headofthe tool and their lower ends formed into cutters G, in combinationwith the strutbrace l?, adapted to seat itself between the legs, thespindle O,carrying the brace, and the extensible system of pivotedlevers L M N, pivoted below to a fixed point and to the head of thespindle O above, all operating substantially as and for the purposeherein described.

6. In a well-boring expanding drill-bit, the divergent spring legs B,having shoulders b and cutters C, and the fixed block E and tube J,suspended from the head of the tool between the legs, in combinationwith the strutbrace P, adapted to seat itself in the shoulders tool andthe lower ends formed into cutters C, 2o said legs having on theirouteredges, above the cutters, the knees D, the fixed fulcrumblock E betweenthe legs, andthe links G, limiting their divergence, and the means forholding them rigidly separated when working, consisting of thestrut-brace P, adapted to find a seat between the legs, the spindle Ocarrying the brace, and the system of extensible pivoted levers L M N,pivoted below to a fixed point and above to the head ofthe spindle,substantially as herein described.

In witness whereof I have hereunto set my hand.

CHARLES C. LANE.

vVitnesses:

C. D. COLE, J. H. BLooD.

